Existing electrolyte solution absorbent polymers are ordinarily produced by adding cross-linking monomers to monomers having a solubility relative to electrolyte solution as an object and polymerizing the cross-linking monomers therewith. In this case, since most of monomers used as raw materials are relatively expensive, and the raw material monomers may partly remain in a product while they are not kept polymerized even after the polymerization, the monomers are inconvenient in respect of cost and safety.
Further, since the existing electrolyte solution absorbent polymers are merely designed and produced for absorbing only specific electrolyte solution as a target, the absorbing power of the polymers for certain kinds of electrolyte solutions out of the specific electrolyte solution is extremely deteriorated. However, in practice, since there exist greatly many cases in which a plurality of kinds of electrolyte solutions need to be simultaneously absorbed, the electrolyte solution absorbent polymers applicable to broad ranges are eagerly desired.
Further, in order to improve the handling property of the aqueous electrolyte solution absorber upon its transportation or storage, a more improvement is demanded so as to make the absorber hardly get out of shape during its transportation or storage.
As sandbags which are materials of construction for preventing the overflow of rivers, lakes and marshes, etc. in flood damages, for instance, linen bags filled with soil have been conventionally used. Since both the weight and volume of such sandbags are large, it has been difficult to convey them. Accordingly, the sandbags have been frequently conveyed one by one through the hands of persons in the site of a disaster or the like. Further, when the sandbags are conveyed from a remote place, the sandbags need to be conveyed by using vehicles and it takes labor to unload the sandbags. Thus, upon generation of a disaster, the water absorbers having the functions of the sandbags need to be rapidly applied to necessary positions at a necessary time, however, the sandbags have been prevented from being rapidly and sufficiently applied due to an inferior transportation property as described above. In addition, the sandbags cannot be inconveniently disposed on risky positions for the persons to convey the sandbags to.
Further, for water absorbers used for removing unnecessary water remaining due to water leakage or flood, etc., fibrous materials such as cloths have been employed. However, when a large amount of water needs to be removed because of the rupture of city water pipes due to the disaster of earthquake, etc., a large-scale flood in a broad area due to a flood damage or the water leakage from the tanks of a factory and so on, the same problems as those of the above-described sandbags have been generated.
Still further, when the sandbags are actually soaked in water, various kinds of electrolytes (sodium salts, phosphate salts, etc.) are eluted from the components of soil in the sandbags. In the water leakage from the factory, water containing electrolyte (aqueous electrolyte solution) may leak. However, since a conventional water absorbent polymer is low in its absorption magnification relative to the aqueous electrolyte solution, there has existed a problem that a performance as the absorber having a function of a sandbag or a function for removing the unnecessary water containing electrolytes cannot be completely achieved.
Furthermore, while, for the water absorbers used for removing unnecessary water remaining due to the water leakage or the flood, etc., fibrous materials such as cloths have been employed, the water absorbers are low in their absorption magnification relative to the aqueous electrolyte solution, the performances of the water absorbers cannot be inconveniently completely exhibited especially when a large amount of water containing electrolytes leaks from a factory.
Under the above-described circumstances, there has been eagerly desired an aqueous electrolyte solution absorber which effectively acts on electrolytes eluted from the components of soil in sandbags, sea water originally containing electrolytes or water leaking from a factory and is small in weight and volume and easily conveyed.